Time has not been kind to Mysteries of the Sith. The game itself is about the same as Dark Forces II and thus pretty decent, but the translation from late-90s CD-ROM to 2016 digital download was clearly not a smooth one. Whenever it switches over to a cutscene or whenever I enter a menu, the game window shrinks to a little 640x480 box. And when the game is "big" it still has a windowed border that cuts off the top part of the screen. Also, the game crashed several times. It's playable, with a little patience, but if it weren't for the blog, I'd have probably washed my hands of it.
I'm not sure about the plot of the game yet. Apparently the light-side ending of Dark Forces II is canonical (it's just as well, because the dark-side one sucked) and Kyle Katarn is mentoring a new Jedi while developing his own powers and aiding the new galactic republic. I don't know much about this Mara Jade character except that in the old expanded universe she was Luke Skywalker's wife, but since that plot point seems unlikely to return in the new movies and probably won't happen in the course of this game, I'm just going to ignore it.
But so far, Katarn hasn't done much of anything. He escaped from a Republic base as it came under attack by some kind of remnant imperial force, but then he landed on an asteroid and has been dicking around ever since. I think the asteroid was weaponized in some way and that's why Kyle is so interested, but it's not clear exactly what the problem is.
Finally, I couldn't help but notice the lack of FMV cutscenes. It doesn't quite feel like a true Dark Forces II expansion without them. Sure, they were cheesy as hell, but they had an earnestness to them that charmed me. The animated cutscenes actually work a lot better and allow for more complex dialogue, but, well, nobody's going to remember them 20 years later.